main() {
  //算术运算符
  num a = 10;
  num b = 3;
  print(a + b);
  print(a - b);
  print(a * b);
  print(a / b);
  print(a ~/ b);
  print(a % b);

  //关系运算符
  print(a > b);
  print(a < b);
  print(a >= b);
  print(a <= b);
  print(a == b);
  print(a != b);

//赋值运算符
  a += b;
  print(a);
  a -= b;
  print(a);
  a *= b;
  print(a);
  a /= b;
  print(a);
  a ~/= b;
  print(a);
  a %= b;
  print(a);

  //逻辑运算符
  print(a > b && a < 10);
  print(a > b || a < 10);
  print(!(a > b));


}
